The new Tom Waits album begins, in very Waitsian fashion, with a racket: a squall of percussive noise that sounds like it was recorded in a freight elevator. During the first decade of his career, Waits established a unique persona and a maudlin sound--he was a singing Bukowski, a barfly balladeer who croaked

romantic songs about skid-row characters, accompanied by piano and strings--but starting with Swordfishtrombones (1983), the Beat poet became a poet of the beat, pop's supreme rhythm freak. He's filled his records with junkyard percussion and close-miked drums whose sound distorts into a muffled boom. He has pushed lurching, old-time musical machines (pump organ, calliope) to the foreground, reveled in the noise of oddball instruments and found sounds (Swiss bells, glass harmonica, "Indonesian seed pod") and hired musicians like Marc Ribot, who plays his guitar a bit like a drum--anything to make his songs clatter like a jalopy navigating an unpaved road.

Real Gone, Waits's nineteenth studio album, brings a new kind of thump. It's there in that album opener, "Top of the Hill," alongside a deejay's turntable scratches and dissonant flashes of electric guitar: a pummeling sound that might easily be mistaken for a computer-generated drumbeat but is in fact the voice of Tom Waits, who borrowed a trick from hip-hop--human beatboxing--and created many of Real Gone's rhythm tracks by huffing into a hand-held tape recorder. Waits has long used his voice, one of the most expressive and unlovely instruments in pop, to channel a rogues' gallery of characters. On the new album, Waits sings both the drunkard's lament and the sound of his drunken stagger. A voice as loud and leathery as any drum has taken its rightful place in the rhythm orchestra.

Waits's beatboxing, and the absence of his trademark piano, bring a whiff of novelty to Real Gone. But the album could hardly be called a departure. Waits is still writing taut little poems about love and death and setting them to tunes that distill Kurt Weill, parlor ballads, circus music, rural blues, urban funk, snatches of Afro-Cuban rhythm and other seemingly incompatible source materials. Unlike many veteran performers, who shuffle record producers and hop between trendy styles in an effort to keep up with the zeitgeist, Waits long ago left the world behind; his post-Swordfishtrombones output has been impressively focused, the work of an artist burrowing deeper into his eccentricities. Despite minor shifts in tone and texture, it's fair to say that Waits has been making the same album for the past twenty-two years.

Of course, no one but Waits has been making that album; he's a genre unto himself. Who besides Waits could dream up "Metropolitan Glide," which slows a James Brown groove to a sinister creep, adds some raggedy guitar picking and serves up a string of Bizarro World dance-floor instructions: "Turn off the sound on your cellular phone/Whip the air like a Rainbow Trout...Show your teeth bray like a calf"? That song, like most on Real Gone, is swamped in noise: feedback, overloaded microphones, fuzzy guitars. It's a sound as thick and lumpy as a bowl of goulash, and listening to it you realize how accustomed your ears have become to the crispness of digital-age pop; of all Waits's perversions, none are more refreshing than his devotion to sonic muck. The mambo-blues song "Shake It" takes the approach to an extreme, setting Waits's lead vocal against Ribot's lead guitar and gradually ratcheting up the distortion on both, until it's nearly impossible to tell one from the other.